This invention relates to an applicator used to insert a sanitary tampon into the vaginal canal of the user.
There has already been proposed an applicator for sanitary tampon, which comprises an outer cylindrical tube and an inner plunger axially movable within the outer cylindrical tube for ejecting a sanitary tampon out of its front end opening into the vaginal canal. It is also well known to provide the outer tube in the form of a cylinder having a substantially uniform outer diameter. Examples of such applicators are described in Japanese Patent Application Disclosure Nos. 1980-155647 and 1980-155648.
The above-mentioned applicators have sometimes encountered the inconvenience such that the applicators are forced back under contraction of sphincteral muscle during introduction of the outer cylindrical tube into the vaginal canal by outstretching the vaginal opening. If such situation occurs in the course of ejecting the tampon out of the outer cylindrical tube, not only the tampon but also the applicator would be no more useful and go to waste. Even if the situation is not so serious, introduction of the outer cylindrical tube into the vaginal canal may sometimes be undesirably delayed.
It is an object of this invention to provide an applicator enabling a sanitary tampon to be reliably introduced into vaginal canal.
According to this invention, there is provided an applicator for sanitary tampon comprising an outer cylindrical tube having openings at front and rear ends, and an inner plunger axially movable within the outer cylindrical tube for ejecting a sanitary tampon out of the opening at the front end of the outer cylindrical tube into the vaginal canal; and
the outer cylindrical tube has an outer diameter thereof gradually increasing rearwardly from the front end until the maximum outer diameter region is reached and then gradually decreasing from behind the maximum outer diameter region wherein the maximum outer diameter region extends within xc2xd of a full length of the outer cylindrical tube as measured from the front end.
According to one preferred embodiment of this invention, said outer cylindrical tube is formed behind the maximum outer diameter region with the minimum outer diameter region.
According to another preferred embodiment of this invention, the maximum outer diameter of the outer tube is in a range of 8-20 mm and the minimum outer diameter of the outer cylindrical tube is in a range of 20-70% of the maximum outer diameter.
According to still another preferred embodiment of this invention, the outer cylindrical tube is shaped to have, behind the minimum outer diameter region, an outer diameter larger than the minimum outer diameter.
According to further another preferred embodiment of this invention, the inner plunger has, at a front end and/or a rear end thereof, an outer diameter larger than an outer diameter at any intermediate point between the front and rear ends.
According to an additional preferred embodiment of this invention, the inner plunger is provided in the form of tube having openings at a front and rear ends thereof.
According to another additional preferred embodiment of this invention, the outer cylindrical tube is flexible transversely of an axis of said outer cylindrical tube behind the maximum outer diameter region.